Question

An object is thrown upward with a speed of 15 m/s on the surface of planet X where the acceleration due to gravity is 2.5 m/s2. How long does it take for the object to return to where it is thrown?

Answer 1

12s

Step-by-step explanation:

the formula is

s = u×t + 0.5×a×t²

where:

s is the displacement of the object at this time (so it's equal to 0)

u is the initial speed

t is the time you have to find

a is the acceleration due to gravity

`0 = 15 (m)/(s) * t + 0.5 * 2.5 \frac{m}{{s}^(2) } * {t}^(2)`

`15 (m)/(s) * t = 0.5 * 2.5 \frac{m}{ {s}^(2) } * {t}^(2)`

`15 (m)/(s) = 1.25 \frac{m}{{s}^(2) } * {t}`

`t = \frac{15 \frac{m}{ {s}^{} } }{1.25 \frac{m}{ {s}^(2) } }`

`t = 12s`